<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Flex Box</title>
    <style type="text/css">
        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        .container {
            width: 100%;
            height: 100%;

            /*align-self: stretch;*/
            /*height: 200px;*/
            /*height: 100%;*/
            background-color: yellowgreen;

            border: 1px solid brown;
            position: absolute;

            display: flex;
            /*!*direction: rtl;*!*/
            flex-direction: column;
            /*justify-content: space-around;*/
            /*align-items: flex-start;*/
            /*flex-wrap: wrap;*/
            /*align-content: space-around;*/
        }

        .element {
            margin: 5px;
            /*width: 50%;*/
            /*height: 50px;*/
            background-color: yellow;
            border: 1px solid brown;

            /*margin: 10px;*/
        }
    </style>
</head>
<body>
<div class="container">
    <div class="element" style="flex: 3">Div01</div>
    <div class="element" style="flex: 7">Div02</div>
    <!--<div class="element" style="width: 200px">Div03</div>-->
    <!--<div class="element" style="flex: 1">Div04</div>-->
    <!--<div class="element">Div05</div>-->
    <!--<div class="element">Div06</div>-->
    <!--<div class="element">Div07</div>-->
    <!--<div class="element">Div08</div>-->
</div>
</body>
</html>